Merge branch 'master' into nested_has_many_through

Conflicts:
	activerecord/CHANGELOG
	activerecord/lib/active_record/association_preload.rb
	activerecord/lib/active_record/associations.rb
	activerecord/lib/active_record/associations/class_methods/join_dependency.rb
	activerecord/lib/active_record/associations/class_methods/join_dependency/join_association.rb
	activerecord/lib/active_record/associations/has_many_association.rb
	activerecord/lib/active_record/associations/has_many_through_association.rb
	activerecord/lib/active_record/associations/has_one_association.rb
	activerecord/lib/active_record/associations/has_one_through_association.rb
	activerecord/lib/active_record/associations/through_association_scope.rb
	activerecord/lib/active_record/reflection.rb
	activerecord/test/cases/associations/has_many_through_associations_test.rb
	activerecord/test/cases/associations/has_one_through_associations_test.rb
	activerecord/test/cases/reflection_test.rb
	activerecord/test/cases/relations_test.rb
	activerecord/test/fixtures/memberships.yml
	activerecord/test/models/categorization.rb
	activerecord/test/models/category.rb
	activerecord/test/models/member.rb
	activerecord/test/models/reference.rb
	activerecord/test/models/tagging.rb

1 files changed, 41 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/coders/yaml_column.rb b/activerecord/lib/active_record/coders/yaml_column.rb
new file mode 100644
index 0000000000..fb59d9fb07
--- /dev/null
+++ b/activerecord/lib/active_record/coders/yaml_column.rb
@@ -0,0 +1,41 @@
+module ActiveRecord
+  # :stopdoc:
+  module Coders
+    class YAMLColumn
+      RESCUE_ERRORS = [ ArgumentError ]
+
+      if defined?(Psych) && defined?(Psych::SyntaxError)
+        RESCUE_ERRORS << Psych::SyntaxError
+      end
+
+      attr_accessor :object_class
+
+      def initialize(object_class = Object)
+        @object_class = object_class
+      end
+
+      def dump(obj)
+        YAML.dump obj
+      end
+
+      def load(yaml)
+        return object_class.new if object_class != Object && yaml.nil?
+        return yaml unless yaml.is_a?(String) && yaml =~ /^---/
+        begin
+          obj = YAML.load(yaml)
+
+          unless obj.is_a?(object_class) || obj.nil?
+            raise SerializationTypeMismatch,
+              "Attribute was supposed to be a #{object_class}, but was a #{obj.class}"
+          end
+          obj ||= object_class.new if object_class != Object
+
+          obj
+        rescue *RESCUE_ERRORS
+          yaml
+        end
+      end
+    end
+  end
+  # :startdoc
+end